1. Field of the Invention
The present invention relates to an embedded Multi Media Card (eMMC), and in particular relates to burn-in test for an eMMC.
2. Description of the Related Art
The MultiMediaCard (MMC) is based on a NAND-based flash memory. Typically, an MMC is used as a storage media for a portable device, in a form that can easily be removed for access by a PC. For example, a digital camera would use an MMC for storing image files. With a card reader (such as an MMC reader), a user can copy pictures to his or her computer.
Based on the MMC standard, an embedded storage solution with an MMC interface, flash memory and controller all in a package is named an embedded Multi Media Card (eMMC). To guarantee the reliability of the flash memory within the eMMC, a burn-in test is required, which is the process by which the flash memory is exercised prior to being placed in service.
FIG. 1 shows a conventional burn-in test design for eMMC. As shown, N eMMCs 102_1-102_N are inserted into N card readers 104_1-104_N, respectively, to be connected to a host 106. The host 106 outputs commands to the command lines of the eMMC 102_1-102_N to operate the eMMCs 102_1-102_N all in a transfer state. The transfer state is designed for a conventional burn-in test.
However, it is difficult to further test heat endurance by the conventional test architecture of FIG. 1. For example, it is not feasible to put the host 106 in an oven or in a refrigerator.
A novel test architecture for an eMMC is called for.